To conduct the research, scientists sourced 10 photos from Google and altered six of them with image editing software. Then they asked more than 700 volunteers whether the images had been manipulated. Here’s one:

Is this photo manipulated?

Click on the image to find out.

Sophie Nightingale, Cognitive Research, 2017

Yes, this image was manipulated in four places: (1) The boat was added, (2) the trees on the left were stretched rightward, (3) trees were added on the right, and (4) the man’s face was retouched. (Pimples were removed, teeth were whitened, eye color was brightened.)

In a second experiment, the scientists developed an online test to judge people’s ability to locate manipulations. They asked participants to tell where an image had been manipulated, regardless of whether people said the image had been altered in the first place. Here’s one of those photos:

Can you spot the changes?

This image has been manipulated in four places. Click for the answer.

Sophie Nightingale, Cognitive Research, 2017

(1) The man’s shadow was shifted, (2) the garbage cans on the right were added, (3) the branches of the tree on the left were stretched rightward, and (4) the man’s face was retouched. (Wrinkles were removed, hair was added.)

In this case, people were able to locate the alterations in the image 56% of the time. Images can influence memories of the past, so if people can’t tell a real photo from a doctored one, bogus images might alter what they believe and remember, the scientists say.